A wireless optical sensor tracks a tiny and disposable reflective target, which is usually placed on the user’s forehead, cap or glasses. The user moves their head and controls the movement of the mouse cursor. When this capability is combined with a mouse button clicking solution and on-screen keyboard software, the HeadMouse can completely replace the functions of a conventional mouse and keyboard.

Headmouse

A headmouse can be operated through the use of a reflective dot being placed on the user's forehead/glasses. If head movement ability is limited the dot can also be placed anywhere on a body part which does have good movement. For instance the dot can be placed on a fist, forearm, foot etc. whatever has the best movement. The tracker can be pointed in many directions. In that sense the term "headmouse" or "headtracker" is unnecessarily limiting and constrained. The rest of this article mainly uses the word "head" but please remember that this also refers to other functioning body movements. When the user moves his/her head, the movement of the headmouse is recognised by an infrared receiver which in turn translates the head movements into cursor movements on the screen. Clicking solutions
Using a headmouse in practice:

In addition to cursor movement another element is required for full mouse functionality. Button clicking. Mouse button selections are made either by using a dwell and click software application whereby the user pauses over the on-screen target for a user definable period of time, at the end of which, a pre-defined button click (left, right, double left, click and drag, scroll etc.) is generated. Alternatively, clicks can also be generated using a physical external switch (link to switches) that can be activated by fists, fingers, arms, foot etc.

Webcam head controlled pointer

Webcam Head Controlled Pointers are the latest and most innovative devices available to the person unable to use the traditional mouse. The user sits in front of the Web Cam and looks at the screen. When the user moves their head the cursor follows in real time. The software automatically transforms detected movements into cursor movements or even into commands. The software includes motion detection systems that are able to detect and analyse any small movements.Typically all the software packages have basic pointer and dwell selection controls and some include spelling gesture control (a nod of the head to the left for a mouse click, for example). One of their big advantages is that no headgear is required. On the negative side they do require top of the range computers to run on.

Free Camera Mouse

There is also a completely free head-tracker solution if you already own a Web-cam. Many laptops already have a built in Webcam. It is called Camera Mouse www.cameramouse.org/index.html . It tracks a unique feature on your face such as the bridge of your nose etc. This works quite well and doesn't require much processing power. However It's not as precise as a dot tracking unit such as the Tracker Pro by Madentec. It doesn't work in the dark or poor lighting conditions but it is well worth a try. It might just work for you.

Examples of commercial head tracking systems

• TRACKER PRO by Madentec tracks the movement of a user’s head, and converts it to mouse cursor movement signals. The user wears a small reflective sticker on the forehead or glasses frame (or hat or baseball cap!) or any other appropriate body part with good dexterity. It is positioned on top of the computer screen or AAC device and emits infrared signals to the reflective dot that in turn reflect the signals back to the tracker. The user’s head movement is measured and converted to mouse movement. The Tracker Pro simply plugs into the USB port and it works instantly. No drivers are required on Windows XP and Vista. The Tracker Pro also works in poor light conditions, even in total darkness. For the dwell and click functionality Madentec sells a solution called Magicursor.

• SMARTNAV is similar to Tracker Pro. A wireless optical sensor tracks a tiny and disposable target that is placed on the user’s forehead or glasses. The user simply moves their head to position the cursor. When this is combined with Smartnav's dwell and click software, and the free Microsoft virtual on-screen keyboard software (in the Accessibility section in Accessories on Windows systems), the functions of a conventional keyboard and mouse can be totally replaced. It enables true hands free control of a computer. SmartNav was designed to complement the natural head motion you already perform when looking around. Moving your head less than a quarter inch easily maneuvers the cursor across your entire screen. The device works well - if you can get your computer to recognise the camera. If you have Vista, make sure you have the latest driver from the NaturalPoint website. SmartNav4 is the latest version (Source: TechReady).
  
  Dwell Clicking. You can left click, double click, drag, right click, and more - with Smartnav's "dwell clicking toolbar" software application.
  You can type on your computer screen with SmartNav's virtual keyboard program.
  
  Switch Input:. You can plug a click switch or a footswitch directly into the back of the SmartNav. With the Y Breakout Cable (included), you can plug in separate click switchesfor left and right clicking.
  
  

  SmartNav 3		SmartNav 4
  Using SmartNav 4 together with a sip+puff switch		User with MS
  Using SmartNav with Grid 2		Using SmartNav with Mac OS X More SmartNav videos . . . . . .

  
  
  
• Head tracking for VR displays using the Wii Remote
  
  
  
  Visit Johnny Lee's website for more information and the software to make it work . . .
  
  

• DREAM MOUSE is a new development that enables two individuals to share equal access to a PC at the same time. Plug Dream-Mouse directly into a USB port and Windows will automatically recognise it and install it on your computer. Dream-Mouse works with Windows 98, 2000, ME and XP. Dream-Mouse uses head movements (or other body movements) to give the user full control over games, e-mail, documents or access to the internet. Dream Racer Blog

• CAP-MOUSE uses motion sensors activated by head movements to position a PC cursor. Cap-Mouse is based on similar technology we designed for the Dream-Racer and Dream-Gamer products. Anyone driving a Dream-Racer car or playing a game on the Sony PlayStation with Dream-Gamer will be able to use Cap-Mouse to send e-mail, access the internet, play games on a PC.
  
  
• Synapse Head Tracker
  
  The Synapse Head Tracking device provides full mouse control of a computer. Requires good headcontrol. Moving one's head moves the cursor on the screen. Activating a 'sip and puff' switch or other external switch makes selections. On-screen keyboards such as WiViK® allow for word processing and other text entry.
  
  You can change the Synapse Head Tracking device from Apple to Windows compatibility just by flipping a switch. Full support for one, two, and three button mice is built in. You can operate the mouse button with the puff switch mounted on the headset or plug other switches into the back of the control box. If the user has acceptable speech then Dragon NaturallySpeaking voice recognition facilitates efficient voice recognition keyboard entry and speech activated mouse button clicks.
  
  More information about Synapse . . .
  

Dwell and Click applications

Point 'N' Click .

Free alternative to clicking software This is a dwell-and-click software solution called point-n-click www.polital.com/pnc/ . This software is extremely feature rich and stable and works on both Windows XP and Vista. This software also works perfectly in conjunction with Madentec and Smartnav tracker hardware. For example, the combination of the $399USD Smartnav tracker (or the Tracker Pro), the FREE point-n-click software and the FREE Microsoft virtual keyboard delivers a very cost effective and functional solution for hands free computing.

MagicCursor2000.

It's for people who can't, or don't want to click the mouse button. It performs all the mouse button functions automatically through software. All you need to be able to do is point: MagicCursor automatically takes care of the rest. It is an ideal companion for the Tracker head operated mouse products. Instead of clicking the mouse button, simply dwell over the item you want to select. After a preset amount of time, MagicCursor will automatically perform the click for you. More information about MagicCursor2000 . . .

Head Pointers

Head Pointers now come in quite a variety of designs. Unlike forehead protrusion pointers, an 'out from the chin' device allows closer proximity to the item being accessed and reduces the head movement needed to activate such a device. It eliminates the barrier imposed by the forehead pointers because it doesn't interrupt either the wearer's field of vision or the full view of the wearer's face.

Zygo Pointer		Using the Zygo Head Pointer
Using a head pointer and a foot mouse		FRS Pointer Image: Forbes Rehab Services

Using head mounted laser pointers to communicate

The Ace-Centre have started to put together a list of currently known head pointer designs, in an attempt to inform the buyer of the capabilities and pitfalls of each particular product. More information . . .